In the general construction of automobile engines, manifolds are connected to the engine's cylinder head with bolts. Usually gaskets are placed between these manifolds and the head so that leakage will not occur when the manifolds are secured to the head with the bolts and the engine operated.
Traditionally there are two manifolds, one being an intake manifold which includes porting for the flow of air and fuel to the combustion chambers of the engine. The other manifold is the exhaust manifold through which the hot combustion products are vented from the engine. In the more conventional engines the exhaust gases are ported from the cylinders through cylinder heads to the exhaust manifold. Often the exhaust manifolds are constructed of cast iron with multiple ports along one side or face which mate or connect to the outlets in the head along with an internal channel therein communicating with all the ports and a common exhaust outlet. Thus the exhaust gases from the engine pass into the individual ports of the exhaust manifold, and then via the channel in the manifold to the outlet to which an exhaust pipe is connected leading to a muffler and thence to a tail pipe. This invention relates to headers which replace such exhaust manifolds.
Exhaust headers are purchased by car enthusiasts to replace the conventional exhaust manifolds for internal combustion engines, for a number of reasons, not the least of which is to reduce the back pressures thereby increasing horse power output and efficiency of the engine. Typically such headers include multiple pipes one of which pipes connect to one of the outlets on the engine's cylinder head with their opposite ends joined in a plenum chamber formed between the distal ends or opposite ends of the pipes and the exhaust outlet that connects to the exhaust pipe.
Various manufacturers make custom headers, but not the car manufacturers; thus, these non-stock products are not uniform and often gaskets must be special ordered when such headers are mounted on engines for which they are designed. As the headers are light weight, that is much lighter than the cast headers, gaskets are usually necessary due to the mechanical distortion caused by the bolt tensions, thermal distortion and dynamic distortion from the effects of both acting together.
One of the objects of the current invention is the provision of custom headers which overcomes the need for gaskets between the cylinder head and the header.
Another object of the invention is the provision of a custom header which is less prone to leakage after it is installed.